What signs of a C-section (cesarean section) site, such as infection, would necessitate immediate medical evaluation for potential postoperative complications?

Warning Signs of C-Section Incision Complications Requiring Immediate Evaluation

Any C-section incision showing purulent (pus) drainage, erythema extending >5 cm from the wound edge, increasing warmth and tenderness, wound separation, or systemic signs (fever >38.5°C, tachycardia >100 bpm) requires immediate medical evaluation for surgical site infection. 1, 2

Critical Red Flags Requiring Urgent Assessment

Local Wound Signs

• Purulent drainage (thick, opaque, yellow-green discharge) from the incision—this is the hallmark of surgical site infection and requires immediate evaluation 1, 2
• Erythema (redness) extending >5 cm from the wound edges, particularly if spreading or worsening 1, 2
• Increasing warmth, tenderness, or induration (hardness) around the incision site 1, 2
• Wound dehiscence (separation of the incision edges) or gaping of the wound 1
• Fluctuance suggesting fluid collection or abscess formation beneath the incision 1

Systemic Signs

• Fever >38.5°C (101.3°F), especially if persistent or occurring after postoperative day 4 1, 2
• Tachycardia >100 bpm at rest 1, 2
• Hypotension or signs of sepsis (altered mental status, decreased urine output) 1

Important Distinction: Normal vs. Abnormal Drainage

• Sanguinous drainage (blood-tinged, watery) alone without other signs does NOT constitute infection and can be normal postoperative healing 2
• Serous drainage (clear, straw-colored) is also typically benign 2
• Only purulent drainage (thick, opaque, foul-smelling) indicates infection requiring intervention 1, 2

Immediate Management Algorithm

Step 1: Clinical Assessment

• Inspect the wound for purulent drainage, erythema extent, warmth, tenderness, and wound integrity 1, 3
• Measure vital signs including temperature, heart rate, blood pressure, and respiratory rate 3
• Assess lochia (vaginal bleeding) for excessive amount, foul odor, or abnormal color suggesting endometritis 3

Step 2: When to Obtain Cultures

• Obtain wound cultures before starting antibiotics if purulent drainage is present or SSI is suspected 1
• Culture results guide targeted antibiotic therapy, though empiric treatment should not be delayed 1, 4

Step 3: Treatment Decision Tree

If purulent drainage OR erythema >5 cm OR systemic signs present:

• Primary treatment is surgical drainage, not antibiotics alone 2
• Open the incision to drain purulent material 1, 2
• Add antibiotics only if there is surrounding invasive infection (erythema/induration >5 cm) AND systemic signs (fever >38.5°C or pulse >100 bpm) 2
• Empiric antibiotic choice: Cefotaxime 1-2 grams IV every 8 hours for moderate to severe skin/soft tissue infections, covering Staphylococcus aureus, Streptococcus species, E. coli, and anaerobes 4

If only sanguinous drainage without other signs:

• Serial wound inspection daily for development of purulent drainage, increasing erythema, or systemic signs 2
• No antibiotics or surgical intervention needed at this stage 2
• Monitor for progression to true infection 2

Step 4: Ongoing Monitoring

• Daily wound checks for at least 30 days postoperatively, as late SSIs (diagnosed after POD 10) occur in 5-10% of cases 5
• Educate patients that persistent symptoms (pain, fever, drainage) warrant medical evaluation even if initially mild 5
• Address barriers to care-seeking: many women don't seek care because they perceive symptoms as not serious enough or face financial/transportation barriers 5

Common Pitfalls to Avoid

Pitfall 1: Treating with Antibiotics Alone

• Antibiotics without drainage have no clinical benefit for established SSIs 2
• The primary therapy is always incision opening and drainage when purulent material is present 1, 2

Pitfall 2: Needle Aspiration of Fluid Collections

• Avoid needle aspiration of suspected hematomas or seromas, as this introduces skin flora and increases infection risk 1
• Surgical drainage under sterile conditions is preferred if intervention is needed 1

Pitfall 3: Missing Deep or Organ/Space Infections

• Superficial wound infections are obvious, but deep incisional SSIs (involving fascia/muscle) and organ/space SSIs (endometritis, pelvic abscess) may present with fever and systemic signs without obvious wound changes 1
• Consider CT imaging if deep infection or abscess is suspected, particularly with persistent fever despite wound management 1

Pitfall 4: Dismissing Late-Presenting Infections

• SSIs can present weeks after discharge, with cumulative prevalence reaching 10% by POD 30 5
• Rare cases of scar abscesses years after C-section have been reported, requiring drainage and sometimes hysteroscopic management 6

Risk Factors Increasing SSI Likelihood

Understanding these helps identify high-risk patients requiring closer surveillance:

• Emergency C-section (25% infection rate vs. 9% for elective) 7
• Prolonged surgery (>1 hour duration) 7
• Significant blood loss (>800 mL) 7
• Signs of intrauterine infection before surgery 7
• Subcutaneous tissue thickness >2 cm (increases seroma/hematoma risk) 8
• Obesity 9, 8

Patient Education Points

Instruct patients to call immediately if they develop:

• Pus or foul-smelling drainage from the incision 1, 3
• Redness spreading beyond the immediate incision area 3, 2
• Fever, chills, or feeling systemically unwell 3
• Increasing pain, warmth, or swelling at the incision site 3, 2
• Wound separation or opening 3

Emphasize that early reporting improves outcomes and that financial concerns should not delay seeking care for these warning signs 5.